Chapter 25 structure and function of cardiovascular system Flashcards
***What is the function of circulatory system?
-Main function is to transport
-Deliver o2 and nutrients to the tissues
-Circulates electrolytes and hormones
-Transport immune substances that contribute to the body defense mechanism
But it also carries out waste products
What does the circulatory system circulate?
Electrolytes and hormones
What does the circulatory system deliver?
Delivers oxygen and nutrients to tissues
What does the circulatory system carry?
-Waste
-Nutrients
-O2
-blood
-
What does the circulatory system regulate?
helps regulate temperature
Which ventricle is anterior?
Right ventricle
Which ventricle is posterier ?
Left ventricle
What are the heart layers?
-Endocardium
-Myocardium
-Pericardium
Describe Endocardium?
-Where the pockets of blood are
-Innermost layer
-Flexible, fibrous connective tissue
Describe myocardium
-Gives heart pumping action
-Cardiac muscle
Describe pericardium?
-wrapper layer
-outtermost layer
What is the pericardial cavity?
-Space between visceral pericardium
-Envelope/wrapper like
- Contains fluid to provode lubercation
What do the heart valves do?
Regulate blood flow through the heart
Where is the (Right) Tricuspid valve located
Between right atrium and right ventricle
Where is the (right) Pulmonic valve located?
Right ventricle and pulmonary artery
Where is the (left) mitral valve located?
Between left atrium and left ventricle
Where is the (left) Aortic valve located?
Left ventricle and the aorta
What is the cardiac cycle?
Term used to describe rhythmic pumping of the heart? (lub dub sound?
What are two parts to the cardiac cycle?
-Systole
-Diastole
What happens during systole?
Ventricles are contracting
What happens during diastole?
Ventricles are relaxing and being filled with blood
What is blood pressure?
blood pressure is the force of your blood pushing against the walls of your arteries
How is blood pressure calculated?
Blood pressure is calculated by cardiac output x pulmonary vascular resistance
co X pvr
Cardiac output x Pulmonary vascular resistance
How do you calculate Cardiac Output?
Stroke volume x heart rate
SV x HR
What is cardiac output?
The measurement of the amount of blood the heart pumps each minute
How do you calculate Pulmonary vascular resistance ?
Afterload
What are the two values of blood pressure?
Systolic and diastolic
Where is systolic and diastolic located?
Systolic-numerator
diastolic- denominator
What is systolic pressure?
Pressure against arterial wall during conractions
What is diastolic pressure?
measures the pressure when your heart is in its resting phase,
What is heart rate?
The number of times the heart beats each minute
What is stroke volume?
The amount of blood being pumped with each bump
What is pulmonary vascular resistance?
The resistance of the pulmonary artery to blood flow from left atrium
**Workload of heart
What is preload?
Preload is Ventricular filling
- The measurement of ventricles filling up
-Blood coming from the body to fill and stretch ventricles
-End volume pressure that stretches right or left ventricle
**Workload of heart
What is afterload?
Afterload is resistance
-The pressure generated in the left ventricle needed to pump the blood out of the heart
**Workload of heart
What is cardiac contractility?
The ability for the heart to contraction without changing its resting (disatole)
What is hemodynamics?
How blood flows in the circulatory system
**Composition of blood vessels
What is the Tunica externa?
-Fibrous and connective tissue that supports the vessels
-wrapper vessel and outermost
**Composition of blood vessels
What is tunica media?
-Responsible for vascular tone
-smooth muscle
-Constricts to regulate and control diameter of the vessel
**Composition of blood vessels
What is the Tunica intima ?
-Hooked on to blood flow
-Thin layer, endothelial cells
**Circulatory system
What is circulatory system?
Closed system where the heart consists of two pumps in series
Consists of Arterial and Venous
what is aterial pressure?
pressure measured within large arteries in the systemic circulation
-Higher pressure
-90-100mm/hg
-This would include systemic circulation
What is venous pressure?
the vascular pressure in a vein or the atria of the heart
-lower pressure
-12mm hg
-Pressure inside your veins
-This would include pulmonary circulation
**Local control of blood flow
What is auto regulation?
-The body changes tone of vessel to get blood where it needs to go
-Happens due to changes in the blood vessel tone because changes in the flow through the vessel or by local factors
What can autoregulation be caused by?
-Lack 02
-Hypermia
-endothelial control
-accumulation of tissue metabolites
**Local control of blood flow
What is long term ?
-If short term doesn’t work,body will create long term effects
What can happen in long term ?
The body can create new vessels, collateral circulation, anastomotic channels
**Microcirculation
What do arteries and arterioles function as?
Distribution system to move blood to tissue (high pressure system )
-Move blood away from the heart to tissues
What is the function of capillaries ?
Work as an exchange system
- transfers gases,nutrients, and waste takes place (smallest)
What’s the function of venues and veins
Serve as collection and storage vessels that return blood to the heart (low pressure system )
-Moves blood to the heart
**Arterial system
Describes arteries
-stretch during a cardiac systole and recoil during diastole
-Thick walled vessels with large amounts of elastic
**arterial system
Describe arterioles
-Serve as resistance vessels of circulatory system
-act as control value through which blood is released as it moves into capillaries
What’s the function if capillaries?
-Connect the arterial and venous segments
-Interstitial fluid exchange
-Controlled by hydrostatic and osmotic pressure
describe lymphatic system
-Main route for absorption of nutrients
-Filters fluid at lymph nodes, and removes foreign particles such as bactersi
-Anything that is left behind is picked up by the lymphatic tissue
-Lymph is derived from interstitial fluid
Function of lymphatic system?
Filters fluid @lymph node and remove foreign particles
** neural control of circulatory function
Where is the neural control of circulatory function located?
Medulla oblongata
** neural control of circulatory function
What is the vasomotor center?
Contains controlling sympathetic- mediated acceleration of heart rate and blood vessel tone
** neural control of circulatory function
What is the cardioinhibitory center?
Contains the third, which controls parasympathetic mediated slowing of heart rate
** Autonomic nervous system
What does sympathetic do
Controls smooth muscle tone of blood vessels
-Norepinephrine is neurotransmitter
** Autonomic nervous system
What does parasympathetic do?
Regulates heart function but not the blood vessels
Acetylecoline- neurotransmitter
What does the central nervous system do?
Regulates vasomotor tone and blood pressure to the brain
What is the cardiac conduction system?
Electricity component of heart
Order of electrical pulse?
1.) SA node(pace maker of heart. 60-100 hb)
2.)Av node(40-60hb)
3.) Bundle of his(20 hb)
4.) right and left bundle branches(20 hb)
5.) Purkinje fibers( 20 hb)
What is noepinerine
vasoconstrictor
What is angiotensin ll
Most powerful vasoconstrictor
What is serotonin?
vasoconstrictor
IMportant role in controlling bleeding
What is prostagladins
vasoconstrictor and vasodilate
What is epinephrine?
Some vasoconstriction and dilate
What is histamine?
Vasodilate
What is bradykinn
Intense vasodilation of arteries, permeability, constriction of venules
